Advice on choosing video card and computer case for custom gaming desktop?

I don't much about computer specs and terms so I need help deciding. I don't need to have the best graphics card, just a decent one, enough to run games within the future years in the lowest settings.



I've been thinking about nVidia GeForce 8 and up series, but I'm not sure what the specs mean on them and such. My budget for the video card would probably be around $120, but if possible, save money. I don't much about ATI series, but I'm not picky about which manufacturer. If possible, please list an nVidia and ATI equivalent and explain it to me. For example, the equivalent of nVidia GeForce series 6 is ATI 1300XT series, and this is better because of... this.



For the casing, I don't understand about the size and the material it's made out of, also if I should get extra fans. I plan on playing quite a lot, and I don't really mind sound. I'm also confused about the brand, type, and color. Does that make a difference?



Here are my wanted parts so far, hopefully it helps about the size:



[Processor]

http://www.newegg.com/Product/Product.aspx?Item=19-115-078



[Motherboard]

http://www.newegg.com/Product/Product.aspx?Item=13-131-716



[Hard Drive]

http://www.newegg.com/Product/Product.aspx?Item=22-136-770|||$110 will get you a HD5770, which is the best you can get for under $140. I max out 90% of todays games on one. The next upgrade from there would be a HD6850 for $150.



Check this build with a HD5770 for just $600. That would last atleast 3 years for mid low settings.

http://gamingrig.blogspot.com/2011/06/60…



This build for $200 more will give you twice the gaming horsepower.

http://gamingrig.blogspot.com/2011/06/75…



Edit:

No it wont be the same. If you want a pre-built computer with the same performance as that $600 PC, you will need to spend around $1000. So it's really not worth it.|||The ATI Radeon 5770 gives you stunning next-gen graphics at an affordable price. Fully compatible with DirectX 11, this powerful graphics card can run all of the latest games without any stuttering or slowdown. It is loaded with advanced rendering technologies that make your games look more realistic than ever before. And thanks to ATI Eyefinity, you can expand your display across three monitors--adding an extra level of immersion to your gaming. With certified drivers for Windows 7, Windows Vista, and Windows XP, the Radeon 5770 will take your gaming experience to the next level.